PySide6-examples: SpreadSheet example

Port pre-existing SpreadSheet example to PySide.

Pick-to: 6.2 6.3
Change-Id: I32d014fbd5e3e406672b6bec2465c6e41c3a6580
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>

1 files changed, 122 insertions, 0 deletions

diff --git a/examples/widgets/itemviews/spreadsheet/spreadsheetitem.py b/examples/widgets/itemviews/spreadsheet/spreadsheetitem.py
new file mode 100644
index 000000000..dc70da883
--- /dev/null
+++ b/examples/widgets/itemviews/spreadsheet/spreadsheetitem.py
@@ -0,0 +1,122 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+from typing import Any, Tuple
+from PySide6.QtCore import QMetaType, Qt
+from PySide6.QtWidgets import QTableWidget, QTableWidgetItem
+
+
+class SpreadSheetItem(QTableWidgetItem):
+    is_resolving = False
+
+    def __init_subclass__(cls) -> None:
+        return super().__init_subclass__()
+
+    def data(self, role: int) -> Any:
+        if role == Qt.EditRole or role == Qt.StatusTipRole:
+            return self.formula()
+
+        if role == Qt.DisplayRole:
+            return self.display()
+
+        t = str(self.display())
+
+        if role == Qt.ForegroundRole:
+            try:
+                number = int(t)
+                color = Qt.red if number < 0 else Qt.blue
+            except ValueError:
+                color = Qt.black
+            return color
+
+        if role == Qt.TextAlignmentRole:
+            if t and (t[0].isdigit() or t[0] == '-'):
+                return int(Qt.AlignRight | Qt.AlignVCenter)
+
+        return super().data(role)
+
+    def setData(self, role: int, value: Any) -> None:
+        super().setData(role, value)
+        if self.tableWidget():
+            self.tableWidget().viewport().update()
+
+    def display(self) -> QMetaType.Type.QVariant:
+        # avoid circular dependencies
+        if self.is_resolving:
+            return QMetaType.Type.QVariant
+
+        self.is_resolving = True
+        result = self.compute_formula(self.formula(), self.tableWidget(), self)
+        self.is_resolving = False
+        return result
+
+    def formula(self) -> None:
+        return str(super().data(Qt.DisplayRole))
+
+    def compute_formula(self, formula: str, widget: QTableWidget, this) -> QMetaType.Type.QVariant:
+        # check if the string is actually a formula or not
+        list_ = formula.split(' ')
+        if not list_ or not widget:
+            return formula  # it is a normal string
+
+        op = list_[0].lower() if list_[0] else ""
+
+        first_row = -1
+        first_col = -1
+        second_row = -1
+        second_col = -1
+
+        if len(list_) > 1:
+            SpreadSheetItem.decode_pos(list_[1])
+
+        if len(list_) > 2:
+            SpreadSheetItem.decode_pos(list_[2])
+
+        start = widget.item(first_row, first_col)
+        end = widget.item(second_row, second_col)
+
+        first_val = int(start.text()) if start else 0
+        second_val = int(end.text()) if start else 0
+
+        if op == "sum":
+            sum = 0
+            for r in range(first_row, second_row + 1):
+                for c in range(first_col, second_col + 1):
+                    table_item = widget.item(r, c)
+                    if table_item and table_item != this:
+                        sum += int(table_item.text())
+
+            result = sum
+        elif op == "+":
+            result = first_val + second_val
+        elif op == "-":
+            result = first_val - second_val
+        elif op == "*":
+            result = first_val * second_val
+        elif op == "/":
+            if second_val == 0:
+                result = "nan"
+            else:
+                result = first_val / second_val
+        elif op == "=":
+            if start:
+                result = start.text()
+        else:
+            result = formula
+
+        return result
+
+    def decode_pos(pos: str) -> Tuple[int, int]:
+        if (not pos):
+            col = -1
+            row = -1
+        else:
+            col = ord(pos[0].encode("latin1")) - ord('A')
+            try:
+                row = int(pos[1:]) - 1
+            except ValueError:
+                row = -1
+        return row, col
+
+    def encode_pos(row: int, col: int) -> str:
+        return str(chr(col + ord('A'))) + str(row + 1)